Mechanisms and significance of microglia-axon interactions in physiological and pathophysiological conditions

Microglia are the resident immune cells of the central nervous system, and are important for cellular processes. In addition to their classical roles in pathophysiological conditions, these immune cells also dynamically interact with neurons and influence their structure and function in physiological conditions. Microglia have been shown to contact neurons at various points, including the dendrites, cell bodies, synapses, and axons, and support various developmental functions, such as neuronal survival, axon elongation, and maturation of the synaptic circuit. This review summarizes the current knowledge regarding the roles of microglia in brain development, with particular emphasis on microglia-axon interactions. We will review recent findings regarding the functions and signaling pathways involved in the reciprocal interactions between microglia and neurons. Moreover, as these interactions are altered in disease and injury conditions, we also discuss the effect and alteration of microglia-axon interactions in disease progression and the potential role of microglia in developmental brain disorders.

Automated summary

Microglia, as the resident immune cells of the central nervous system, not only play important roles in pathophysiological conditions but also interact dynamically with neurons in physiological conditions, influencing their structure and function. These immune cells contact neurons at various points and support developmental functions such as neuronal survival, axon elongation, and synaptic circuit maturation. Recent findings on the functions and signaling pathways involved in the reciprocal interactions between microglia and neurons are reviewed, along with discussions on the altered interactions in disease conditions and the potential role of microglia in developmental brain disorders.